I have Shimano GRX groupset and the rear shifting has been pretty erratic lately. Got a new chain and cassette, replaced cables and housing, cleaned and lubricated everything, and it's still not working great. I wonder if something is broken/worn inside the shifting/brake lever (ST-RX600). Does that ever happen (after 10 000 km)? I am an experienced home-mechanic but never took a drop bar shifting lever apart, judging by the looks it's a bit scary. #GRX #gravel #cycling #HomeMechanic